Materials such as diamond film obtained by chemical vapor deposition (CVD diamond), polycrystalline diamond (PCD), crystalline boron nitride (CBN) and polycrystalline boron nitride (PCBN) are among the hardest materials known. Cutting tools made with tip inserts of PCD or other hard materials are difficult to manufacture. Typical cutting tool processes require two grinding operations, a rough grind and a finish grind, carried out with different abrasive wheels. Many of the conventional abrasive tools employed in roughing and finishing these materials include metal-bonded superabrasive. Metal-bonded abrasive tools generally grind fewer parts per hour than glass bonded tools.
Glass-bonded superabrasive tools have attractive temperature characteristics, but tend to be brittle and wear more rapidly than metal bond tools. In addition, glass-bonded diamond tools can have performance deficiencies caused by poor diamond-to-glass bonding. Further, existing methods for fabricating glass-bonded diamond tools typically require high temperatures, long cycles and non-oxidizing or reducing atmospheres.
Therefore, a need exists for grinding tools capable of roughing or finishing hard workpieces, as well as for methods for manufacturing such tools, that reduce or eliminate the above-mentioned problems.